This document describes the various releases of the Helium compiler that were
published on Hackage since 2014. Pre-Hackage and pre-Cabal versions of Helium
are not documented. For information on these, please contact the authors
of Helium. More information on the compiler and the ideas underlying it can
be found on the Helium website, located at 

   http://foswiki.cs.uu.nl/foswiki/Helium/WebHome
   
ABOUT VERSION 1.8

This is the first version of Helium to be deployed through Cabal and Hackage.
The main changes with respect to earlier versions of Helium is how the compiler
is invoked, the parameters it supports, the use of a configuration file that
governs its behaviour, and of course the platform independence achieved through
the use of Cabal. The package offers three executables: ``texthint'' (the
text-based command-line interpreter, i.e., our version of ghci), ``runhelium''
(a wrapper for executing lvm object code files), and of course ``helium'', the
compiler itself. 


ABOUT VERSION 1.8.1

Version 1.8 of Helium does not work with the graphical programming environment
``Hint'' that Arie Middelkoop developed some years ago. Since the release of
Helium 1.8 on Hackage we found that some people would still like to use Hint. 
This version of Helium works well with Hint (version 1.8.1 and higher). The
integration is achieved through a program ``heliumpath'' that exposes the
necessary path information that Hint needs to locate the libraries and the
configuration file.

Hint is not available through Hackage. The jar-file for Hint can be downloaded
from the Helium website. The sources of Hint are publicly available from the svn 
repository that also stores the source code of the Helium compiler and all
associated tools. Again, see the links on the Helium website.